The subject matter disclosed herein relates to radiographic detectors for non-invasive imaging and particularly to the use of a reflector with the radiographic detectors.
In radiographic systems, an X-ray source emits radiation (e.g., X-rays) towards an object or subject (e.g., a patient, a manufactured part, a package, or a piece of baggage) to be imaged. As used herein, the terms “subject” and “object” may be interchangeably used to describe anything capable of being imaged. The emitted X-rays, after being attenuated by the subject or object, typically impinge upon an array of radiation detector elements of an electronic detector. The intensity of radiation reaching the detector is typically dependent on the attenuation and absorption of X-rays through the scanned subject or object. At the detector, a scintillator may convert some of the X-ray radiation to lower energy optical photons that strike detector elements configured to detect the optical photons. Each of the detector elements then produces a separate electrical signal indicative of the amount of optical light detected, which generally corresponds to the incident X-ray radiation at the particular location of the element. The electrical signals are collected, digitized and transmitted to a data processing system for analysis and further processing to reconstruct an image.
After X-ray excitation, the scintillator continues to emit a broad spectrum of wavelengths of optical photons for an extended period of time (e.g., microseconds to milliseconds) known as an afterglow signal. Different wavelengths of light from the afterglow signal may persist for different amounts of time after the X-ray excitation, with some wavelengths persisting longer than other wavelengths. The afterglow signal may result in artifacts in the reconstructed image.